VOCO presenterar "Direct layered dual shade composite veneer restorations treating a high stress area"

Description of Treatment Including Rationale for Choice of Restorative Material

The Patient presented with what now appears to be iatrogenic wear of his 31BI and 41BI regions. As if this case was focusing on the restoration of upper central incisors, there would be no need to worry about adding length as long as: 1) there was enough room and 2) one could establish a balanced anterior guidance shared amongst the lower four incisors during protrusive and lateral excursive function (if canine guidance was absent). The strategy would be to reduce and recontour the cingulum region of 21-12 as much as possible without exposing the metal substructure in order to give a slight amount of room for increased resistance form of the composite veneer restorations. With the patient’s consent, this was completed.

The lower anterior sextant was isolated with a split dam technique, comprised of #2A Hu-Friedy rubber dam clamps on teeth 34 and 44 and a Roeko rubber dam (Coltene). Following the minimal infinity bevel preparations on teeth 31BI and 41BI, Mylar strips were utilized distal to 31 and 41 and each tooth was subjected to micro air abrasion with 50 micron aluminum oxide on the facioincisal aspect in order to increase the amount of micromechanical retention. Each tooth was then etched with 33% H3PO4 (aq) followed by the application of three coats of Optibond Solo Plus (Kerr) before air-thinning to evaporate the solvent. This was light-cured with a Radii LED light source (SDI).

A putty palatal matrix was not created as there was no previous experience with the patient who regularly was seen by another dentist in the practice. Hence, a Mylar strip was applied to tooth 31 initially in a wrap-around fashion, prebending the strip to create defined line angles at the distolingual and mesiolingual line angles. The matrix was stabilized on the lingual aspect with a finger as the initial lingual shelf was applied freehand against the Mylar strip. This palatal shelf layer should measure approximately 0.3mm thickness and will act as the scaffold for the restoration. The Mylar strip was now removed and the composite veneer applied in layers first to the cervical half of the tooth, feathering incisally before addition of the second ball of composite material to the incisal half.

Artistic scalloping and dentinal detail was sculpted into the incisal 1.5mm with the goal of allowing for some optical characterization in the final product. These scalloped regions were “filled in” using GrandioSO Flow Incisal (VOCO). The final enamel layer was then applied in a single ball increment, burnished and feathered using a Greenstein instrument, brushed and shaped interproximally with the Ronvig silicon brush and blended seamlessly over the surface of the entire tooth. It is important at this stage to always be viewing the proposed restoration from the incisal view. This will allow for identification of excess thicknesses of material not visible from the frontal view as well ensure adequate material for good definition of mesial and distal line angles. Incremental addition worked to minimize polymerization shrinkage of the resin composite, which is a remarkably low 1.61% volumetric shrinkage in GrandioSO’s case.

Few “body” dentin shades are able to simultaneously opaque and optically blend to the respective environment. Often, multiple dentin shades are required to create the block-out effect and elevate the value of the restoration before needing to select an enamel-like microfill to replace the enamel and allow light penetration into the tooth for visual dimensionality. I was pleasantly surprised at the “universality” of GrandioSO and its ability to be a chameleon, whether of dentin or enamel.

The final layers not only restored slightly the lost tooth volume from iatrogenic attrition, but also created an imperceptible restoration. At this point, the patent contact was confirmed, and the interdental region finished with a 12b scalpel blade and polishing initiated using Epitex strips (GC America). After confirming patent contacts, pencil markings were placed over the facial surfaces defining the line angles to be preserved. Primary and secondary anatomy was defined using needle-point fine diamond burs (Mani Diaburs) and large, coarse Soflex discs (3M), both without water irrigation1. The restorations were polished with the polishing system Dimanto (VOCO) at 5000rpm to high shine. Overall, the patient was pleased with a fine, well polished, biomimetic result that we knew would need to be shortened again slightly according to the occlusion. The important factor is that the new restorations not only have increased resistance form, but by selecting this nanohybrid composite with outstanding physical properties, both clinician and patient can rest assured not only that the restoration will perform well over the long-term, but also look good doing it.